The Recent Resurgence of the Electric Car The zero-emissions e-car went extinct a century ago. Now it is back in a big way, thanks to a complete redesign of the usual sedan's innards. There’s nothing under the hood. Or trunk. You have to crawl under a Tesla to see the few working parts. Here I analyze this vastly simplified sedan and its supercharger network, with comparisons to early e-cars and to plug-in hybrids. William H. Calvin WCalvin@UW.edu WilliamCalvin.org
URBAN MYTH Electric Vehicles (EVs) were not originally golf carts and utility vehicles.
Electric Vehicles were invented in the 1890s by appending motor and batteries to carriages. By 1900, 40% of “horseless carriages“ were EVs. A Baker Electric was part of the first White House fleet of cars. (1909 poster)
The Seattle Electric Car Club met monthly on Capitol Hill.
The Second Coming of the Electric Car (1996) GM’s EV -1, b.1996, d.2005
HYBRIDs since the 1997 Prius Wimpy gas engine but with acceleration boosted by torque from an electrical assist. Small battery recharged by braking or gasoline motor, not your electrical outlet. Doubled the miles per gallon. But still, gasoline powered.
Low electric-only range from P lug-in H ybrid EV s (PHEVs) From Sierra Club, July 2013 p54
X Low electric-only range from P lug-in H ybrid EV s (PHEVs) From Sierra Club, July 2013 p55
What one usually sees under the hood Hybrids cram in stuff for 2012 Camry electrical as well. 2012 Camry Hybrid
The 3 rd Coming of all-electric cars Nissan LEAF since 2009 Tesla Roadster since 2008 (200 miles) Mitsubishi i-MiEV 2013 Honda FIT 100 mile range
100 mile range
Looking under the hood of a LEAF, you see lots of EV stuff shoe-horned into the usual space. But in a Tesla Model S, it’s difficult to locate anything to see.
This, too, is an electric car. 2013 Tesla Model S Range 300 miles (500km)
W hile Tesla’s 2013 sedan looks like a luxury sedan, it represents a complete re-think, showing how EVs can be vastly simpler — and thus be more reliable, needing less maintenance.
Pop open the hood on a Tesla…
Pop open the hood on a Tesla, “The Microwave” see only storage space (the “frunk”).
The front end of the Tesla Model S has been engineered to be a long crumple zone in the event of head-on collisions. And besides, there is no big engine to be pushed back into the passenger cabin.
Pop open the rear of a Tesla Roadster and you see the working part of the car.
Pop open the rear of a Tesla Model S and you see …
Pop open the rear of a Tesla Model S and you see hatchback- like storage space. Suppose the motor is under here?
The well is big enough for two 5-yr-olds.
WHERE’S THE MECHANICAL STUFF? Hint: Crawl Under the Car
Complexity due to using fossil fuel.
The missing motor
The Tesla Model S fluid cooling/heating battery is in the floor for battery and motor of the car. Can be swapped for a fully- charged battery in 90 Swapping ought to be good for sec, half the time it fleets that work a car three takes to fill up with shifts: taxi , police , etc. gasoline.
Fixed reduction gear No gearshift, even for R everse (they do it electrically) AC motor Inverter (AC to DC, DC to AC, regenerative braking)
This stripped-down model still shows most of the moving parts.
From Gas to Hybrid to PHEV adds complexity at each stage. An evolutionary dead end? That seems likely, given the simplicity achieved by Tesla’s designers in the Model S .
Not “Disruptive Technology” so much as Good Design Cannot appreciate the Tesla designers’ achievement without making a list of all of the things they were able to leave out.
There are over 10,000 parts in a conventional car. Many can cause the engine to fail. In Tesla’s AC induction motor, there is only one moving part : the spinning shaft (plus a few ball bearings). About 90% of all electric motors use Nikola Tesla’s design.
A stunning simplification of car design is possible if the gasoline aspect is completely abandoned. In Tesla’s EV: No spark plugs and wiring harness • No ignition system, carburetor, air filter • No tailpipe, muffler, catalytic converter; no • emission inspections. No fuel tanks, no oil drips or oil changes • No transmission (no gears to shift) • No driveshaft to make noise • No starter motor, no idle, almost silent engine. •
Tesla’s Model S also has a number of innovations that are unrelated to EVs per se. (Any manufacturer could have pioneered them.)
No key anymore (just a fob, but shaped like a Tesla). Nissan LEAF still has an On-Off Button. Not Tesla — just shift into D or R and go.
Turn-by-turn navigation Thumbwheel & 2 buttons Two Push for P ark, touchscreen down for D, windows or up for R. one big one Two display screens
Best backup camera yet. And you can leave it on while driving if you like. Makes an excellent rear- view mirror for blind spots.
3G data connection to internet
Overnight gets you another 55 miles from 110 V outlet.
Overnight on a 220 outlet (now available at some hotels and all RV parks) charges completely.
Full “tank” from 120 V outlet takes 2.5 days
Electricity is cheaper than gas • Full tank (lasts 300 miles) of gas costs $70 • Full recharge (lasts 300 miles) costs $10 at the $0.12/kwh average US rate • Washington State now charges $100/yr for EV tabs to substitute for state gasoline tax (taxes are about 14% of fuel costs) Abroad, fuel taxes are much higher. Tesla should do well in Europe and Asia, likely half of sales in a few more years.
Tesla Superchargers are free charging stations strategically placed on well-traveled corridors (2/3 of a full charge in a half hour).
July 1 Eight new Superchargers off I-5 just north of the Skagit River (falling) bridge. Centralia soon.
Smartphone app allows car monitoring and some remote control. iPhone app shown
Heat or cool Tesla remotely. Find your car iPhone app shown
The Android version of the Tesla App Nissan LEAF has an app as well.
Some Supercharger Sites Will Swap Batteries 22 gallon refueling time 1st Tesla time at fast pump 2 nd Tesla time Swap cost set equal to local price of tank of gas
The Supercharger Network Summer 2013 in operation under construction (200-mile radius)
The Supercharger Network Winter 2013 in operation under construction (200-mile radius)
The Supercharger Network Sometime 2014 in operation under construction (200-mile radius)
The Supercharger Network Sometime 2015 in operation under construction (200-mile radius)
PUSHING AIR ASIDE Kinetic energy imparted to air =½mV² 2x K.E. Driving 70 mph 50 x 50 = 70 x 70 = 2,500 4,900 rather than 50 50 mph reduces range RANGE in miles 335miles 70 mph by 100 miles 235 miles because air resistance doubles . SPEED in MPH
Curve is for Tesla, but similar for any car. PUSHING AIR ASIDE Driving 75 mph rather than 60 RANGE in miles 60 mph reduces range 285 miles 75 mph 70 miles , from 215 miles 285 to 215. SPEED in MPH http://www.teslamotors.com/sites/default/files/graph1.jpg
PUSHING AIR ASIDE SLOW DOWN: Easy range extension rule Each 10 mph decrease in speed gains 50 miles in “full - tank” range on a level road. “Half - tank” left? Each 10 mph decrease in speed gains 25 miles in remaining range. “Quarter - tank” left? Each 10 mph decrease in speed gains 12 miles in remaining range.
Links at TeslaMotors.com
So, 21 st -Century EVs are no longer just golf carts but proper sedans. What’s next? Can a minivan or SUV be far behind?
Tesla Model S (now) Model X (late 2014)
With doors open, you can stand up straight inside (if under 6’2”).
FROM THE BUSINESS PAGE: Tesla, the Company Tesla Model S is now selling better than all others in the Audi-BMW- Lexus-Mercedes class of $60,000 to $90,000. Tesla is also trying to change the model for sales and service, keeping everything in-house. So no dealers (who make most of their money on “service”). You order a Model S via the web, usually not in the showroom (most are in malls).
Forbes June 2013
My first two digital cameras were from Kodak, in 1998 and 2000. …
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